Chapter 7: The CCS project

The news came less than six months after the Norwegian government had taken the momentous decision to build a series of such power stations incorporating carbon capture and storage technology (CCS). The initiative was a perfect example of a vital element in Norwegian energy policy: that high environmental standards and ambitions should be a strong incentive for technological innovation.

A new gas-fired power plant and methanol production facility to be built at Tjeldbergodden, the industrial complex in mid-Norway, would provide carbon dioxide (CO2) to the Draugen and Heidrun offshore oil and gas fields. Power from the plant would also supply the offshore fields, reducing CO2 and nitrogen oxide (NOx) emissions from these installations to virtually nothing. The project could potentially store approximately 22.5 million tonnes of CO2 annually in two different fields.

The various elements of the project were to be phased-in over several years between 2010 and 2012. “Establishing this CO2 value chain is technologically and commercially challenging”, the statement continued, and the project would therefore depend on substantial Government funding and the involvement of industrial stakeholders and electricity users in the region.

It would also help Norway to meet international and national climate policies by increasing energy supplies  and in particular contributing to long-term power balance in mid-Norway  while addressing the issue of related CO2 emissions. Statoil was already a pioneer in CO2 storage through Sleipner in the North Sea, Snøhvit in the Barents Sea and In Salah in Algeria: a vital corporate example of the importance of technology for value creation in the petroleum sector.

Historic controversy
For years the issue of whether to build gas-fired power stations at all had been hugely controversial: so much so that, in 2000, Norway’s then-government became the first in the world to fall over a dispute related to global warming as a result of parliament’s insistence on building gas power stations without carbon capture. Five years later, in October 2005, the decision to go for CCS technology at the first such plant  at Kårstø on the west coast  was virtually the first major announcement by Norway’s latest centre-left coalition. Incredibly, Kårstø was to be the country’s first fossil fuel generating capacity.

Kårstø was to be permitted to operate for a few years while the technology was put in place; future plants would be required to have the technology as a condition of their licences. The oil and energy ministry takes the view that the use of CO2 as a medium to enhance recovery from producing fields on the Norwegian continental shelf is a positive development in resource management and in economic terms as contributing to the advance of carbon capture and storage technology  even though CO2 will compete with other mediums, such as water and natural gas itself, already performing that function.

However, realizing such a CO2 value chain is demanding, as it implies added challenges compared to pure storage: in particular, how to make sure that sufficient volumes of CO2 are brought from large point sources to the fields offshore at the right time in the lifespan of the field. Ultimately, CO2 used for enhanced oil recovery will be permanently stored in the abandoned reservoirs. International cooperation is crucial in efforts to develop cost-effective solutions for capture, injection and permanent storage of CO2  hence Norway’s involvement in such bodies as the Carbon Sequestration Leadership Forum (CSLF) and the International Energy Agency (IEA), as well as the European Union Framework Programmes.

Norway already has over a decade’s experience of geological storage of CO2, extracted from gas production on Statoil’s Sleipner West field and stored 1000 metres below the seabed. Comprehensive research and monitoring activities associated with this project suggest that injection and permanent storage of CO2 in subseabed geological structures is safe and reliable. The Snøhvit field, where carbon injection and storage started in April 2009, is expected to provide further experience of CO2 storage and its behaviour in underground geological reservoirs.

Tjelbergodden and Mongstad
It is worth noting here that Tjelbergodden, the proposed site of a gas-fired power plant, represents yet another chapter in an already fascinating history  with or without the planned development. Inaugurated in 1997, Tjeldbergodden is already Europe’s biggest plant of its kind, supplying 13 per cent of Europe’s methanol needs and corresponding to 25 per cent of Europe’s total production capacity for the alcohol. Gas from the Heidrun field is transported via the 250-kilometre Halten pipeline, and the finished product is then transported by ship to customers in Europe, where it is used as a component in the chemical industry.

In addition to the methanol plant, the industrial complex comprises an air gas factory producing liquid nitrogen, oxygen and argon, and a small plant for liquefied natural gas (LNG) production. A full-scale CO2 capture and storage project is underway at Mongstad, a west coast oil refinery and industrial site, where construction of a European centre for the development and testing of carbon capture technology is well underway. “With the Mongstad CCS project we move from the research/small scale phase to actual construction of a full scale CO2 capture facility”, the ministry says.

Mongstad’s aim, according to Statoil, which is responsible for the development and operations phases, will be “to offer an arena for purposeful development, testing and qualification of carbon capture technology [and] contribute to the international dissemination of the results of this work, so that the cost and risk of full-scale carbon capture plants can be reduced”. The centre will have an annual capacity for capturing about 100,000 tonnes of carbon dioxide from flue gases and access to facilities for technology testing and verification at a size close to industrial scale. Start-up is planned for the end of 2011 or early 2012, after which the work on technology development and testing is to begin.

	Now catch your carbon....

Gassnova and CLIMIT
A new government company, Gassnova, was created in 2007 as a subsidiary of the ministry responsible for looking after governmental interests and technological development associated with the capture, transport, injection and storage of CO2. With the Research Council of Norway, Gassnova is joint administrator of the national CCS programme, known as CLIMIT.

Gassnova says its main task is “to manage governmental interest and support technology development within the area of CO2-management (capture, transport, injection and storage of CO2)... based on a vision of promoting environmentally friendly gas power technology with CCS in Norway through innovation, technology development and demonstration in demo and full scale”. A major aim is to develop ways of reducing the costs linked to CCS.

The primary objective of the CLIMIT programme is “to commercialize power generation from fossil fuels with CO2 management through research, development and demonstration”. To this end, the scheme supports testing and demonstration projects the aim of which is “to develop cost-efficient and future-oriented technology concepts for CO2 management”. This includes the development of know-how and solutions for:

• CO2 capture before, during or after power production
• compression and handling of CO2
• transport of CO2
• long-term storage of CO2 and other areas of application.

CLIMIT co-funds projects “seen as having an obvious commercial potential and which include a market-oriented business plan”. The main challenge lies in “encouraging major industry players to invest sufficient resources in technology development as a basis for industrial development while at the same time enabling Norway to fulfil its environmental commitments. “The key to promoting strong industry involvement is to create confidence that new markets for products and services will emerge on a scale large enough to justify such substantial investment on the part of industry. Another challenge is that Norway has only a few national technology suppliers capable of such investment, making cooperation with international industry essential.”  However, given the international race to develop the best, most cost-efficient technologies, Norway is in an excellent position to help thanks to its experience with the geological storage and monitoring of CO2 in the Sleipner field.

Main objectives
Nationally, CO2 management is considered in connection with three main objectives: to reduce emissions of greenhouse gases associated with the combustion of fossil fuels, to maintain a satisfactory power balance by using gas power, and to increase the use of Norwegian gas for domestic economic growth and power production. The technical aim, simply stated, is to carry out CO2 separation from flue gases in connection with gas-fired power plants and to establish a value chain for the use of CO2 to enhance oil production  or, as CLIMIT has put it, to develop “profitable gas power technology with CO2 management in Norway.”

About NOK 3.4 billion is earmarked in 2010 for the CCS projects at Mongstad and Kårstø, research and development of CCS technologies, and international projects: an increase of almost 80 per cent from the previous year. “The Test Centre Mongstad (TCM) is one of the main instruments in the Norwegian Government’s policies to combat climate change”, says Terje Riis-Johansen. “It is an important step on the way to develop technologies which may reduce CO2 emissions. The goal is that the project will make a significant contribution to the development of CCS in Norway as well as internationally.” An action plan for international promotion of development and implementation of CCS aims “to encourage acceptance for CCS as an instrument to curb emissions [and] to promote CCS internationally”.

Technological options
While the terms of reference for funding technological development are defined throughout the entire value chain from power
production to storage, the main technological challenges involve power generation on the one hand and CO2 capture on the other. The development of power technology is closely linked to the development of gas and steam turbine technology. The gas turbine is the most important component, and the technology is dominated by a few technology owners at the international level. Certain future processes may also require turbines based on media consisting of a high percentage of water vapour and/or CO2. Turbines must be developed for these processes. In the international arena, substantial investments are being made in further development of conventional gas and steam turbines.

Traditionally, the power processes involving CO2 capture are divided into three categories: post-combustion, specifically amine-scrubbing, where CO2 is purified after combustion using chemicals (amines); precombustion (CO2 is purified prior to combustion to oxy-fuel), and removal of CO2 during the combustion process. However, some innovative and/or “hybrid” processes integrate capture in a way that does not fit into any of these categories. Current international research involves all these processes; but there are no clear technology winners at present, and it looks like this work will continue along multiple technology tracks for many years to come.

Capture technology is ordinarily based on the absorption of CO2 in a solvent (e.g., amine-based in connection with post- and pre-combustion capture) and condensation of water vapour from a mixture of water vapour and CO2 (with oxyfuel combustion). Some technologies use membranes and reactions of metal oxides with a carbonate, as well as chemical looping, where the combustion process in the gas turbine cycle has been replaced by a dual-reactor combustion system that divides combustion into separate oxidation and reduction processes.

Available and deployable
In the short term, the aim of technological development is to reduce the cost of implementing market-ready post-combustion technology while developing better absorption chemicals; longer term, the hope is that new technologies based on e.g. fuel cells and/or membranes might achieve a significantly higher efficiency factor and further reduce expenses.

One approach to the development of power generation and CO2 capture differentiates between technologies which can be realized within five or ten years and those most to likely take longer. In the first category, post-combustion capture technology is already available and should be readily deployable, although the need for drastic upscaling entails uncertainty. Another advantage of post-combustion is that the capturing equipment can be retrofitted and the method can be used for CO2 capture from other industrial point sources.

There is no need to develop gas turbines separately, and improvements in efficiency can be expected in line with the general development of the technology. The capture plant can be built independently of the gas-fired power plant so as not influence its operability. A great deal has already been invested in this technology by the likes of Aker, SINTEF and K-lab, Statoil’s measurement and technology laboratory at Kårstø, which the company describes as “a unique facility for R&D, testing and qualification of process equipment used in hydrocarbon production and transport”.

Pre-combustion capture through the reforming of natural gas and power production is also based on mature technology; however, developing more compact reformers and developing low-emission NOx burners for H2-rich fuel are challenges. One advantage in the long term is that power production can be combined with large-scale H2 production. Little new technology is required for the reformer or gas turbine.

Technological development requiring an uncertain but probably longer timetable comprises a wide range of technologies. The common denominator is that the processes are known, but components must be modified or developed to be adapted to the process. New technologies that can increase energy efficiency and/or cut costs significantly will be among those targeted for long-term development. There are a number of possibilities based on integrated and hybrid processes with a view to post-combustion, pre-combustion and oxy-fuel-based technologies. The criteria for these projects focus mainly on the potential for reducing risk and enhancing energy efficiency and/or cutting costs significantly. Most such projects are currently at the R&D stage, and involve a substantial funding risk.

Transport and logistics
This area includes transportation by vessel or pipeline and pressure setting. CO2 transportation is currently handled by companies such as the global chemicals giant Yara for industrial purposes, generally using familiar technology. A large-scale scheme for CO2 management requires a significant upscaling of existing transportation solutions. Alternative technologies have been proposed but not tested on an industrial scale.

The challenges lie in reducing the cost of transportation and terminal management as well as establishing a flexible logistics scheme. It is known that the CO2 composition (especially the pollution content) has an impact on the phase equilibrium diagram for CO2 and can thus indirectly affect transportation properties. It may be of interest to fund projects that aim to obtain more experimental data on the fundamental thermodynamic properties of CO2 mixed with other gases and to quantify the effect this has on pressure and temperature requirements during pipeline transportation.

International attention currently focuses on three CO2 storage methods: geological, ocean or mineral storage. The Intergovernmental Panel on Climate Change (IPCC) singles out geological storage as the most suitable method for safe, permanent storage. Norway also has the potential to implement mineral storage on a small scale as the country has good access to relevant silicate minerals; however, this technology is still in the research stage.

Most of the technology elements involved in geological storage have been inherited from oil activities and are thus to a large extent available. The adaptation of technology for CO2 storage takes place under the auspices of different demonstration projects, where EU projects associated with Sleipner CO2 injection have been very important. Norway is in the forefront of this work thanks to the efforts of Statoil and Norwegian research groups in connection with EU and other international collaborative projects.

Fostering greater awareness of the benefits of geological storage as a storage method that neither poses a threat to the environment nor to humans is a key task. This is particularly important with regard to land-based storage facilities. Offshore storage facilities will have to comply with requirements for documentation and follow-up set out in international agreements, which in turn will generate a need for verification of methods.  Most of the countries that do have a national strategy for CO2 management consider geological storage to be the most feasible method of storing CO2. Geological storage is expected to be implemented as a CO2 management policy instrument from around 2015.

For Norway, some degree of mineral storage might be possible owing to the country’s abundant access to relevant silicate minerals. However, this technology is still at the research stage, requiring verification of the speeds of chemical reactions and an analysis of the impacts on energy and the environments. Other possible storage methods also call for further research.

Seal of approval
Reports by the NPD, Gassnova and Gassco leave little doubt that carbon dioxide can be stored in large quantities on the Norwegian continental shelf. Thorough studies of the geological formations are necessary to establish that safe disposal and storage of CO2 is possible. A suitable geological site is one in which there are large volumes of sandstone or some other reservoir rock that is well sealed so that gas and liquid cannot leak. The largest such volumes of sand and sandstone on the NCS are located in the Utsira formation and underlying Skade formation near the Sleipner field, and the Johansen formation under the Troll field.

The Utsira formation is currently used for a variety of purposes including storage of CO2 from Sleipner and as a source of water for water injection on Oseberg. The advantage of the Utsira and Skade formations is that they have nearly unlimited volumes of sandstone; the Utsira formation has a good seal in the Sleipner area and Statoil has proven that it can function as a storage site.

It is uncertain whether the Utsira formation is suitable for future large-scale storage of Europe’s CO2 emissions, but the work indicates that there is more than adequate storage capacity in the area surrounding Sleipner both to cover Sleipner’s needs and to store emissions from Kårstø, Mongstad and other Norwegian industrial sites. The advantage of the Johansen formation is that it forms a deep, closed structure where injected CO2 cannot leak to the surface. The most serious uncertainty is whether there may be a risk that CO2 could leak to Troll; but the NPD’s mapping indicates that this is very unlikely.

Monitoring of the behaviour of the CO2 storage facility is an absolute necessity. At an early stage, a multinational research project, Saline Aquifer CO2 Storage (SACS), collected three years’ worth of relevant data, modelling and verifying the distribution of the CO2 in the Utsira Formation, and developing prediction methods for the long-term movement of the CO2. Time-lapse 3D seismic data were acquired in 1994, prior to injection, and again in 1999, 2001 and 2002 with, respectively about 2.3, 4.3 and 5.0 million tonnes of CO2 in the reservoir. The data show the precise subsurface location of the CO2 plume and confirm that the CO2 is confined securely within the storage reservoir.

The SACS programme has been concluded, but the more recent CO2STORE, an EU Fifth Framework project, has continued to investigate the relevance of this work to other aquifers in Europe, terrestrial as well as offshore. The Utsira Formation is by no means an unusual geological formation in terms of its storage potential, and the Sleipner operation represents just one of many subsurface storage scenarios.